This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cognitive dysfunction is a leading cause of disability in MS, exacting a tremendous socioeconomic and interpersonal toll. Unfortunately, the course of cognitive impairment in MS remains unclear. This study will focus specifically on patients currently exhibiting measurable cognitive deficits who are still engaged in occupational and social responsibilities. While the term mild cognitive impairment(MCI) has been used to identify elderly patients at risk for the development of Alzheimers disease, we believe the concept of MCI can be applied to a specific group of cognitive impaired patients with MS. The goal of this project is to evaluate the course of cognitive deterioration in MS patients receiving standard clinical care and to identify neuroradiological and clinical correlates of this cognitive decline.